How do medications treat bed-wetting?

In general, doctors prescribe medications only for older children who continue to wet the bed; younger children usually outgrow the problem without treatment. Desmopressin acetate (DDAVP) is the most commonly prescribed drug. It works by increasing the child's production of a natural hormone that tells the body to make less urine during sleep. If bed-wetting is happening because the child has a small bladder, the drugs oxybutynin (Ditropan) or hyoscyamine (Levsin) may help. Imipramine (Tofranil) is an antidepressant drug that works by changing the child's sleep pattern and by increasing the time the child's bladder can hold urine and by reducing the amount of urine produced. This drug can cause mood changes and sleep problems, and overdoses can be fatal, so it is used only when other drugs do not help.